Stumbling on the Usborne "Introduction to Computer Programming - Basic for Beginners" book in the library bookmobile that came to my school was probably the first domino that set off the rest of my life in computing. I owe a lot to that book. When I had the book checked out my family didn't have a computer at home so I had to imagine what it'd be like to do the things in my head until I managed to get some time in the school computer lab to try out some of the exercises in the book. Being able to tell the computer what to do just felt so powerful to me.